Image processing apparatus, image pickup apparatus, and image processing method

Abstract

An image processing apparatus includes a memory storing instructions, and a processor configured to execute the instructions to acquire distance information about an in-focus position, and perform filter processing using an aberration filter determined based on the distance information and optical information about an optical system, for image data acquired using an image sensor. The aberration filter has a parameter for adjustment that makes closer to each other a characteristic of a first blurred image formed on an image plane due to defocus on a close distance side of the in-focus position, and a characteristic of a second blurred image formed on the image plane due to defocus on an infinity side of the in-focus position.

What is claimed is: 
     
         1 . An image processing apparatus comprising:
 a memory storing instructions; and   a processor configured to execute the instructions to:   acquire distance information about an in-focus position, and   perform filter processing using an aberration filter determined based on the distance information and optical information about an optical system, for image data acquired using an image sensor,   wherein the aberration filter has a parameter for adjustment that makes closer to each other a characteristic of a first blurred image formed on an image plane due to defocus on a close distance side of the in-focus position, and a characteristic of a second blurred image formed on the image plane due to defocus on an infinity side of the in-focus position.   
     
     
         2 . The image processing apparatus according to  claim 1 , wherein the optical information includes information about at least one of an aperture diameter, zoom, and focus. 
     
     
         3 . The image processing apparatus according to  claim 1 , wherein the optical information includes information about an aberration state on the image plane. 
     
     
         4 . The image processing apparatus according to  claim 1 , wherein the parameter is a parameter for sharpening processing or blurring processing that makes closer to each other a spatial frequency characteristic of the first blurred image and a spatial frequency characteristic of the second blurred image. 
     
     
         5 . The image processing apparatus according to  claim 1 , wherein the parameter is a parameter based on a combined function of an optical transfer function of the first blurred image and an inverse function of an optical transfer function of the second blurred image. 
     
     
         6 . The image processing apparatus according to  claim 1 , wherein the parameter is a parameter for processing that makes closer to each other blurred sizes or blurred shapes of the first blurred image and the second blurred image, which have the same degree of the defocus. 
     
     
         7 . The image processing apparatus according to  claim 1 , wherein the processor is configured to acquire an aberration characteristic based on the distance information and the optical information, and
 wherein the parameter is a parameter based on the aberration characteristic.   
     
     
         8 . The image processing apparatus according to  claim 7 , wherein the processor is configured to acquire the aberration characteristic from a lens apparatus having the optical system, an image pickup apparatus having the image sensor, or an external device. 
     
     
         9 . The image processing apparatus according to  claim 1 , wherein the distance information is information about a defocus amount detected by an imaging-surface phase-difference detecting method using the image sensor. 
     
     
         10 . The image processing apparatus according to  claim 1 , wherein the distance information is information about a defocus amount detected by a phase-difference detecting sensor. 
     
     
         11 . The image processing apparatus according to  claim 1 , wherein the distance information is information about an object distance detected by a distance sensor. 
     
     
         12 . The image processing apparatus according to  claim 1 , wherein the processor performs the filter processing for each divided area in the image data. 
     
     
         13 . The image processing apparatus according to  claim 1 , wherein the processor is configured to acquire the number of taps of a filter kernel in the filter processing, and does not perform the filter processing in a case where it is determined that the number of taps is insufficient. 
     
     
         14 . An image pickup apparatus comprising:
 an image sensor;   a memory storing instructions; and   a processor configured to execute the instructions to:   acquire distance information about an in-focus position, and   perform filter processing using an aberration filter determined based on the distance information and optical information about an optical system, for image data acquired using an image sensor,   wherein the aberration filter has a parameter for adjustment that makes closer to each other a characteristic of a first blurred image formed on an image plane due to defocus on a close distance side of the in-focus position, and a characteristic of a second blurred image formed on the image plane due to defocus on an infinity side of the in-focus position.   
     
     
         15 . The image pickup apparatus according to  claim 14 , wherein the optical information includes information about at least one of an aperture diameter, zoom, and focus. 
     
     
         16 . The image pickup apparatus according to  claim 14 , wherein the optical information includes information about an aberration state on the image plane. 
     
     
         17 . An image processing method comprising the steps of:
 acquiring distance information about an in-focus position, and   performing filter processing using an aberration filter determined based on the distance information and optical information about an optical system, for image data acquired using an image sensor,   wherein the aberration filter has a parameter for adjustment that makes closer to each other a characteristic of a first blurred image formed on an image plane due to defocus on a close distance side of the in-focus position, and a characteristic of a second blurred image formed on the image plane due to defocus on an infinity side of the in-focus position.   
     
     
         18 . The image processing method according to  claim 17 , wherein the optical information includes information about at least one of an aperture diameter, zoom, and focus. 
     
     
         19 . The image processing method according to  claim 17 , wherein the optical information includes information about an aberration state on the image plane.